New tetranuclear manganese clusters with [MnMn(III)] and [MnMn] metallic cores exhibiting low and high spin ground state.

Abstract

Two tetranuclear mixed-valent clusters, [MnMn(III)Cl(Ph3CCOO)4(CH3OCH2CH2O)4(CH3CN)]·0.4C6H5CH3·0.6CH3CN () with an unprecedented [MnMn(III)] core and [MnMnCl4(CH3OCH2CH2O)6] (), were synthesized and characterized by single-crystal X-ray diffraction and magnetic measurements. Their properties were analyzed in the framework of phenomenological modelling and DFT calculations, showing acceptable agreement between theory and experiment. Both building blocks [MnMn(III)] and [MnMn] provide good examples of bipartite systems with the lowest ST = 1/2 and highest ST = 9 magnetic ground states available for them. The topology of the magnetic interactions in the [MnMn(III)] core provides a suitable template for the molecular qubit implementation and the stability of the spin-1/2 ground state strongly depends on the antiferromagnetic Mn(II)-Mn(II) coupling.